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Task/Happy-numbers/Sidef/happy-numbers.sidef

@@ -0,0 +1,15 @@
+func happy(n) is cached {
+    static seen = Hash()
+
+    return true  if n.is_one
+    return false if seen.has_key(n)
+
+    seen{n} = 1
+    happy(n.digits »**» 2 -> sum)
+}
+
+var count = 0;
+Inf.times { |i|
+    happy(i) ? say i : next
+    ++count == 8 && break
+}